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A080231 as a simple table

na(n)
1-1
2-2
3-3
4-4
5-9
6-11
7-17
8-82
9-86
10-89
11-259
12-1031
13-1493
14-3088
15-18107
16-3128320
17-4245574
18-4430458
19-6692218
20-6908807
21-20282631
22-55597679
23-73203786
24-80410013
25-92821351
26-192936649
27-5039379072
28-30234138756
29-55272287466
30-202248991637

[-1,-2,-3,-4,-9,-11,-17,-82,-86,-89,-259,-1031,
 -1493,-3088,-18107,-3128320,-4245574,-4430458,
 -6692218,-6908807,-20282631,-55597679,-73203786,
 -80410013,-92821351,-192936649,-5039379072,
 -30234138756,-55272287466,-202248991637]